1. Field of the Invention
This invention relates to a drainage tube for draining body fluids from a body cavity. More particularly, this invention relates to a drainage tube adapted for insertion into a body cavity through an access thereto made by surgical procedure wherein the drainage tube is of the type including an elastic, flange-like projection at the inlet end of the tube so that the flange-like member may be inserted into the body cavity through the surgical access to prevent the tube from being inadvertently displaced from the body cavity.
2. Discussion of the Prior Art
U.S. Pat. No. 3,807,409 provides a medical ventilation tube which is useful for surgical ventilation and as a drain from the middle ear. The device is constructed of a flexible rubber material in a tubular shape having an inner and outer flange, the inner flange of which is substantially larger in diameter but thinner than the outer flange. The outer flange includes a special upstanding lip which assists in the grasping and removal of the tube. The construction and shape of this ventilation and drain tube limits its usefulness for insertion into the middle ear, i.e. ear drum, of the human ear and access to other body cavities is generally not possible.
German OS No. 30 02298 describes a drainage tube which also includes elastic flanges of variable sizes and shapes at both ends thereof. The shape of this drainage tube is designed to allow it to be inserted into an access leading to relatively narrow body cavities. The flanges, when viewed in a peripheral direction, may be subdivided into several parts in order to facilitate its insertion and removal. In addition, this design allows for the ingrowth of mucous membrane below the middle piece of the tube, for example from the nose into the maxillary sinus or vice versa.
In practice, these dual flange drainage tubes have several drawbacks. In the case of insertion and removal into body cavities of relatively difficult accessability, it is often not possible for the surgeon to control and coordinate hand/eye movement. Accordingly, in these cases, insertion and removal is accomplished essentially only with the help of the sense of touch or feel. However, the use of auxillary tools, such as a pair of pincers or forceps, to assist in handling the drainage tube is often not possible in view of the presence of the rear or outer flange.
Another disadvantage with these prior art drainage tubes is the fact that the opening of the drainage channel of the tube may be covered up by parts of the body wall located in the vicinity of the drainage tube. This could result in the disturbance or even complete stoppage of the drainage flow.